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Distannene
Organotin chemistry is the scientific study of the synthesis and properties of organotin compounds or stannanes, which are organometallic compounds containing tin–carbon bonds. The first organotin compound was diethyltin diiodide (), discovered by Edward Frankland in 1849. The area grew rapidly in the 1900s, especially after the discovery of the Grignard reagents, which are useful for producing Sn–C bonds. The area remains rich with many applications in industry and continuing activity in the research laboratory. Structure Organotin compounds are generally classified according to their oxidation states. Tin(IV) compounds are much more common and more useful. Organic derivatives of tin(IV) The tetraorgano derivatives are invariably tetrahedral. Compounds of the type SnRR'R''R have been resolved into individual enantiomers. Organotin halides Organotin chlorides have the formula for values of ''n'' up to 3. Bromides, iodides, and fluorides are also known, but are less importa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trimethyltin Chloride
Trimethyltin chloride is an organotin compound with the formula . It is a white solid that is highly toxic and malodorous. It is susceptible to hydrolysis. Synthesis Trimethyltin chloride can be prepared by the Redistribution (chemistry), redistribution reaction of tetramethyltin with tin tetrachloride. : This redistribution reaction is typically performed with no solvent because high temperatures are required and purification is simplified. A second route to involves treating the corresponding Organotin chemistry#Organotin oxides and hydroxides, hydroxide or oxide (in the following reaction, trimethyltin hydroxide ) with a halogenating agent such as hydrogen chloride or thionyl chloride (): : Uses Trimethyltin chloride is used as a source of the trimethylstannyl group (). For example, it is a precursor to vinyltrimethylstannane () and indene, indenyltrimethylstanane (see Transition metal indenyl complex): : : An example of an Organolithium reagent, organolithium reagent reacti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geminal Diols
In chemistry, the Descriptor (Chemistry), descriptor geminal () refers to the relationship between two atoms or functional groups that are attached to the same atom. A geminal diol, for example, is a diol (a molecule that has two Alcohol (chemistry), alcohol functional groups) attached to the same carbon atom, as in methanediol. Also the shortened prefix ''gem'' may be applied to a chemical name to denote this relationship, as in a ''gem''-dibromide for "geminal dibromide". The concept is important in many branches of chemistry, including Chemical synthesis, synthesis and spectroscopy, because functional groups attached to the same atom often behave differently from when they are separated. Geminal diols, for example, are easily converted to ketones or aldehydes with loss of water.Peter Taylor (2002)''Mechanism and synthesis'' Book 10 of ''Molecular world''. Open University, Royal Society of Chemistry; . 368 pages The related term ''vicinal (chemistry), vicinal'' refers to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lithium
Lithium (from , , ) is a chemical element; it has chemical symbol, symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard temperature and pressure, standard conditions, it is the least dense metal and the least dense solid element. Like all alkali metals, lithium is highly reactivity (chemistry), reactive and flammable, and must be stored in vacuum, inert atmosphere, or inert liquid such as purified kerosene or mineral oil. It exhibits a metallic luster (mineralogy), luster. It corrosion, corrodes quickly in air to a dull silvery gray, then black tarnish. It does not occur freely in nature, but occurs mainly as pegmatite, pegmatitic minerals, which were once the main source of lithium. Due to its solubility as an ion, it is present in ocean water and is commonly obtained from brines. Lithium metal is isolated electrolysis, electrolytically from a mixture of lithium chloride and potassium chloride. The Atomic nucleus, nucleus of the lithiu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argon
Argon is a chemical element; it has symbol Ar and atomic number 18. It is in group 18 of the periodic table and is a noble gas. Argon is the third most abundant gas in Earth's atmosphere, at 0.934% (9340 ppmv). It is more than twice as abundant as water vapor (which averages about 4000 ppmv, but varies greatly), 23 times as abundant as carbon dioxide (400 ppmv), and more than 500 times as abundant as neon (18 ppmv). Argon is the most abundant noble gas in Earth's crust, comprising 0.00015% of the crust. Nearly all argon in Earth's atmosphere is radiogenic argon-40, derived from the decay of potassium-40 in Earth's crust. In the universe, argon-36 is by far the most common argon isotope, as it is the most easily produced by stellar nucleosynthesis in supernovas. The name "argon" is derived from the Greek word , neuter singular form of meaning 'lazy' or 'inactive', as a reference to the fact that the element undergoes almost no chemical reactions. The complete oc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organometallics
''Organometallics'' is a biweekly journal published by the American Chemical Society. Its area of focus is organometallic and organometalloid chemistry. This peer-reviewed journal has an impact factor of 3.837 as reported by the 2021 Journal Citation Reports by Thomson Reuters. Since 2015 Paul Chirik is the editor-in-chief of ''Organometallics''. He is an American chemist and the Edwards S. Sanford Professor of Chemistry at Princeton University, and associate director for external partnerships of the Andlinger Center for Energy and the Environment. He writes about the catalysis of hydrocarbons. Past editors-in-chief are Dietmar Seyferth and John Gladysz. Retrieved on 2014-07-30. This journal is indexed in |
2,2'-Bipyridine
The comma is a punctuation mark that appears in several variants in different languages. Some typefaces render it as a small line, slightly curved or straight, but inclined from the vertical; others give it the appearance of a miniature filled-in figure placed on the baseline. In many typefaces it is the same shape as an apostrophe or single closing quotation mark . The comma is used in many contexts and languages, mainly to separate parts of a sentence such as clauses, and items in lists mainly when there are three or more items listed. The word ''comma'' comes from the Greek (), which originally meant a cut-off piece, specifically in grammar, a short clause. A comma-shaped mark is used as a diacritic in several writing systems and is considered distinct from the cedilla. In Byzantine and modern copies of Ancient Greek, the " rough" and "smooth breathings" () appear above the letter. In Latvian, Romanian, and Livonian, the comma diacritic appears below the letter, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronegative
Electronegativity, symbolized as , is the tendency for an atom of a given chemical element to attract shared electrons (or electron density) when forming a chemical bond. An atom's electronegativity is affected by both its atomic number and the distance at which its valence electrons reside from the charged nucleus. The higher the associated electronegativity, the more an atom or a substituent group attracts electrons. Electronegativity serves as a simple way to quantitatively estimate the bond energy, and the sign and magnitude of a bond's chemical polarity, which characterizes a bond along the continuous scale from covalent to ionic bonding. The loosely defined term electropositivity is the opposite of electronegativity: it characterizes an element's tendency to donate valence electrons. On the most basic level, electronegativity is determined by factors like the nuclear charge (the more protons an atom has, the more "pull" it will have on electrons) and the number and locatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordination Compound
A coordination complex is a chemical compound consisting of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of chemical bond, bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many metal-containing chemical compound, compounds, especially those that include transition metals (elements like titanium that belong to the periodic table's d-block), are coordination complexes. Nomenclature and terminology Coordination complexes are so pervasive that their structures and reactions are described in many ways, sometimes confusingly. The atom within a ligand that is bonded to the central metal atom or ion is called the donor atom. In a typical complex, a metal ion is bonded to several donor atoms, which can be the same or different. A Ligand#Polydentate and polyhapto ligand motifs and nomenclature, polydentate (multiple bonded) ligand is a molecule or ion that bonds to the central atom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ester
In chemistry, an ester is a compound derived from an acid (either organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group () of that acid is replaced by an organyl group (R). These compounds contain a distinctive functional group. Analogues derived from oxygen replaced by other chalcogens belong to the ester category as well. According to some authors, organyl derivatives of acidic hydrogen of other acids are esters as well (e.g. amides), but not according to the IUPAC. Glycerides are fatty acid esters of glycerol; they are important in biology, being one of the main classes of lipids and comprising the bulk of animal fats and vegetable oils. Lactones are cyclic carboxylic esters; naturally occurring lactones are mainly 5- and 6-membered ring lactones. Lactones contribute to the aroma of fruits, butter, cheese, vegetables like celery and other foods. Esters can be formed from oxoacids (e.g. esters of acetic acid, carbonic acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxide
Hydroxide is a diatomic anion with chemical formula OH−. It consists of an oxygen and hydrogen atom held together by a single covalent bond, and carries a negative electric charge. It is an important but usually minor constituent of water. It functions as a base, a ligand, a nucleophile, and a catalyst. The hydroxide ion forms salts, some of which dissociate in aqueous solution, liberating solvated hydroxide ions. Sodium hydroxide is a multi-million-ton per annum commodity chemical. The corresponding electrically neutral compound HO• is the hydroxyl radical. The corresponding covalently bound group of atoms is the hydroxy group. Both the hydroxide ion and hydroxy group are nucleophiles and can act as catalysts in organic chemistry. Many inorganic substances which bear the word ''hydroxide'' in their names are not ionic compounds of the hydroxide ion, but covalent compounds which contain hydroxy groups. Hydroxide ion The hydroxide ion is naturally produced ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloride
The term chloride refers to a compound or molecule that contains either a chlorine anion (), which is a negatively charged chlorine atom, or a non-charged chlorine atom covalently bonded to the rest of the molecule by a single bond (). The pronunciation of the word "chloride" is . Chloride salts such as sodium chloride are often soluble in water.Green, John, and Sadru Damji. "Chapter 3." ''Chemistry''. Camberwell, Vic.: IBID, 2001. Print. It is an essential electrolyte located in all body fluids responsible for maintaining acid/base balance, transmitting nerve impulses and regulating liquid flow in and out of cells. Other examples of ionic chlorides include potassium chloride (), calcium chloride (), and ammonium chloride (). Examples of covalent chlorides include methyl chloride (), carbon tetrachloride (), sulfuryl chloride (), and monochloramine (). Electronic properties A chloride ion (diameter 167 pm) is much larger than a chlorine atom (diameter 99 pm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
